1. Field of the Invention
The present invention relates to a junction box and a junction box forming method, in which the junction box can connect and distribute a large number of wire harnesses intensively in the case of cabling the wire harnesses in a vehicle or the like.
2. Description of the Related Art
In a junction box mounted in a vehicle, a junction box body is configured as below. Single-layer or plural-layer wiring boards, on which desired circuits are configured by cabling bus bars and electric wires, are stacked on a wiring plate. The wiring plate having the wiring boards stacked thereon is covered with an upper cover and an under cover, and thus the junction box body is configured primarily. There is a junction box of a form, in which a control board serving as an electronic control unit is mounted on the wiring plate. The junction box body having the wiring plate and the control board formed therein as described above is accommodated in a casing provided in an engine room or the like at the time of being mounted in the vehicle or the like. In this case, electronic components for external connection, such as relays, fuses and connectors, are embedded on a front surface of the junction box body.
The casing accommodating the junction box body is divided into an upper case and a lower case. The junction box body is accommodated in the lower case in a state where the upper case is open, and then the upper case covers over the junction box body. On the junction box body accommodated in the casing, locking means is provided therewith so as not to rattle due to vibrations during running of the vehicle and the like.
However, in the conventional junction box, though the junction box body is accommodated in the casing, dew condensation occurring in the casing or on the cover surface drops as water droplets in winter and so on. In this case, the junction box body is formed to have flat surfaces, for example, formed to be a cuboid. Hence, the electronic components for external connection are set to project from the front surface of the junction box body. Therefore, the electronic components embedded on the front surface of the junction box body are splashed with the water droplets having dropped to the casing.
As described above, each surface of the junction box body is a flat shape. Thus, when the upper case is opened and the junction box body is taken out of the casing, in a state where one operator holds the junction box body tightly by both hands, another operator has released a lock of the locking means. Accordingly, when the junction box body is taken out, a plurality of operators have been required, and work efficiency has been low.
It is an object of the present invention to provide a junction box and a junction box forming method, which prevent electronic components for external connection from being splashed with water droplets by forming a visor on an upper end of the junction box body. It is another object of the present invention to provide a junction box and a junction box forming method, which can take the junction box body out of the casing by setting the visor provided on the upper end of the junction box body as a grip.
The first aspect of the present invention provides a junction box comprising: an upper case; a lower case disposed under the upper case; and a junction box body accommodated between the upper case and the lower case, the junction box body comprising: an upper cover having an embedding stage provided thereon for externally connected electronic components; an under cover fitting to the upper cover; a wiring plate disposed between the under cover and the upper cover; wiring boards disposed between the wiring plate and the upper plate, fixed to the wiring plate, stacked in a plurality of stages, and having an insulating plate; and a control board body having a substrate and fixed to the wiring plate, wherein the junction box body is accommodated between the upper case and the lower case to allow the embedding stage to be a front surface in an accommodation direction, and wherein an expanded portion having a projection amount from the embedding stage to above is formed on an upper end of the embedding stage, the projection amount being larger than projection amounts of upper ends of the electronic components attached on the embedding stage, and the substrate is accommodated in the expanded portion.
The second aspect of the present invention provides a junction box according to the first aspect of this invention, wherein the junction box body comprises: first locking means for engaging the junction box body with the lower case and for detaching the junction box body to the lower case from the above; and second locking means for engaging with the first locking means, wherein the first locking means is provided on a side surface of the junction box body and the second locking means is provided on an inner surface of the lower case, the inner surface corresponding to the side surface of the junction box body.
The third aspect of the present invention provides a junction box according to the first aspect of this invention, wherein the control board body comprises a terminal block, the terminal block is constituted of a first divided block and a second divided block, and adjacent ends of both the first divided block and the second divided block constitute a superimposed portion.
The fourth aspect of the present invention provides a junction box according to the third aspect of this invention, wherein the control board body further comprises a substrate connector, the substrate connector is provided independently of both the substrate and the terminal block.
The fifth aspect of the present invention provides a junction box according to the third aspect of this invention, wherein the terminal block is attached in substantially orthogonal to a plane direction of the insulating plate.
The sixth aspect of the present invention provides a junction box according to the fifth aspect of this invention, wherein the terminal block is fastened and fixed to the wiring plate with a screw when the substrate is mounted on the wiring plate.
The seventh aspect of the present invention provides a junction box according to the third aspect of this invention, wherein the substrate is disposed on the wiring plate in an erected state, and the terminal block is provided in substantially orthogonal to a plane direction of the substrate.
The eighth aspect of the present invention provides a junction box according to the first aspect of this invention, wherein the wiring plate has a rectangular shape and is formed of a hard resin, and a plurality of cabling paths having electric wires cabled thereon are formed on a back surface of the wiring plate.
The ninth aspect of the present invention provides a junction box according to the first aspect of this invention, wherein a heat-shielding partition wall for shielding between a power unit and a control unit is provided in the expanded portion.
The tenth aspect of the present invention provides a junction box forming method comprising the steps of: accommodating a junction box body in a lower case to allow an expanded portion of the junction box body to be disposed above; fitting an upper case to an outer circumference of the lower case from above of the lower case; engaging a lock hook of the upper case and a first engaging projection of the lower case with each other; coupling partner connectors to a connector outlet and a substrate connector of the junction box body through an aperture; cabling a wire harness between an upper semicylinder portion and a lower semicylinder portion; disposing a closing member on the aperture; engaging a lock hook of the closing member and a second engaging projection of the lower case; engaging first lock pieces of both sidewalls in a Y direction of the junction box body with engaging convex portions provided on an inner surface of the lower case; and elastically abutting second lock pieces of both sidewalls in an X direction of the junction box body against an inner surface of a ceiling of the upper case and a bottom of the lowercase.